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Theoretica chimica acta

, Volume 29, Issue 4, pp 359–374 | Cite as

Couplage vibronique et anisotropie paramagnétique dans un complexe cubique 2T2 soumis à un champ trigonal

  • O. Kahn
  • S. F. A. Kettle
Commentationes

Vibronic coupling and paramagnetic anisotropy of a cubic complex2T2 subjected to a trigonal field

Abstract

The influence of vibronic coupling on the average paramagnetism and the paramagnetic anisotropy of a cubic complex, the electronic ground state 2T2 of which is perturbed by a trigonal field, is investigated. It is necessary to introduce the following parameters: the spin-orbit coupling coefficient λ, the vibronic coupling coefficient x, the frequency ħωg3 of the E modes of vibration, the splitting Δ of the 2T2 level in the trigonal field and the covalence parameter k.

For given x and \(\varrho \left( { = \frac{{3\lambda }}{{2h\omega _\varepsilon }}} \right)\), the influence of the vibronic coupling is more important if in the trigonal field the electronic ground state of the complex is 2E than if it is 2A. For given x and v (=Δ/λ), the smaller ¦ρ¦, the greater the influence of vibronic coupling. The respective effects of vibronic coupling and covalence are compared. Finally, the case of the first row transition-metal complexes is briefly discussed.

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Copyright information

© Springer-Verlag 1973

Authors and Affiliations

  • O. Kahn
    • 1
  • S. F. A. Kettle
    • 2
  1. 1.Ecole Nationale Supérieure de Chimie de ParisParisFrance
  2. 2.School of Chemical SciencesUniversity of East AngliaNorwichEngland

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